Clinkering apparatus



May- 19, 1925.

R. D. PIKE CLINKERING APPARATUS Filed June 13, 1923 Evenor. Jififz'ke M r (7m 4%;

after): EJJZ Patented May 19, 1925.

UNITED STATES ROBERT D. PIKE, OF SAN FRANCISCO, CALIFORNIA.

CLINKERING APPARATUS.

Application filed June 13, 1923. Serial No. 645,168.

To all whom it may concern:

Be it known that I, ROBERT D. PIKE, a citizen of the United States, residing in the city and county of San Francisco and State of California, have invented certain new and useful Improvements in Clinkering Apparatus, of which the following is a specification.

The hereinafter described invention relates to an apparatus for the clinkering or melting of calcined or raw mixes for making cement or magnesite or similar material whereby a high aluminous or highly refractory cement, and equally so, a very high grade of dead-burned magnesite may be produced at moderate cost. In the carrying out of my invention there is associated with the clinkering apparatus a calcining furnace preferably of the stationary type provided interiorly with superposed hearths, over which hearths' work rabble arms for propelling or conveying the raw material to be treated through the calcining apparatus.

For an understanding of the invention reference should be had to the accompanying drawings wherein- Fig. 1 is a longitudinal sectional View of the improved clinkerer having associated therewith a calcining element partly broken away and, having associatedwith the discharge end of the clinkerer a cooling element through which the treated material discharged from the clinkerer passes for cooling purposes.

.Fig. 2 is a vertical sectional view taken on the line A-A, Fig. 1 of the drawings and viewed in the direction of the arrow.

Fig. 3 is a longitudinal sectional plan view partly broken away disclosing the mechanism for imparting longitudinal reciprocating movement to the vibratory bed of the clinkerer. v

In the drawings, the letter A is employed to designate a vertically disposed stationary calcining element of the'multiple hearth me-' chanical stirred vertical type and, B designates a cooling element having an interior construction substantially the same as that of the calcining element A. These elements being of the usual construction and forming no portion of the present invention, call for no specific description thereof, as to the construction.

The clinkering apparatus comprises a main stationary longitudinally disposed open-bottomed furnace G provided with insulated side walls 1 and an insulated front end wall 2, which said end wall is carried by a transversely disposed support 3 projected from the side walls 1. The front wall 2 is of a height less than the back wall 4 of the furnace so as to leave when the bottom of the furnace is provided a space 4 below its lower edge for the escape or outflow of the clinkered or molten material treated Within the clinkering apparatus. The rear or back wall 4: of the clinker-ing furnace is provided with an opening 5 through which is extended a feed spout 6 for the delivery of calcined material or hot calcines from the calcining element A into the clinkering furnace. The clinkering furnace is supported or upheld by means of the bed plates 5' and the fixed vertical columns 6, Fig. 2 of the drawings. The arched roof wall 7 of the clinkering furnace is provide with a series of openings or holes 8, through each of which is extended one of a series of electrodes 8, comprising a three 7 phase air arc circuit. These electrodes are preferably of carbon and they are connected up by any suitable mechanical and electrical means (not shown) andare designed to maintain arcs in air in close proximity to the bed of material undergoing treatment within the clinkering furnace.

The clinkering furnace is provided with a longitudinall reciprocating or vibratory hearth comprising in the present case a cast iron bed plate 9, a refractory bed 9 mounted thereon and refractory side walls 10. The rear end of the bed plate 9 is extended or projected beyond the inner end wall of the clinkering furnace to serve as a founda tion for supporting a suitable vertically disposed structure 11, which in turn rigidly supports tl1(3 -ifdll1g tube or spout 6 and a receiving cone 15 connected thereto. Where the feeding cup tube or spout 6 enters the clinker-ing furnace, it is provided with a Water cooling sleeve 14. The entire vibratory hearth of the furnace as well as the feed tube carried thereby is supported on pivoted posts or links 15, one of which pivotal posts or'links is held against a fixed stop 16 by means of the tension exerted by a spring 17 and from the said post or llnk there is extended inwardly a stud 19, which a variance of rotative speed imparted to the shaft 18'. It is obvious that the means for imparting vibratory movement to the hearth of the furnace may be situated or located at any desired point found to be most convenient for the operation of the hearth.

By preference, the receiving cone 13 and the'feed tube 6' are constructed of some heat resisting alloy.

During operation, the hot calcines or cal cined material discharging from any suitable type of calcining furnace and preferably of the mechanically stirred vertical type, are conveyed by the discharge pipe 20 into the receiving cone 13 and the vibration given thereto by reason of the vibratory movement imparted to the hearth of the clinkering furnace feeds the calcines or calcined material into the electric clinkering furnace through the tube 6 in a continuous stream as the same discharges from the calcining element. The calcines or calcined material once deposited upon the vibrating hearth of the clinkering furnace advance progressively forward through the said furnace and pass beneaththe electric arcs maintained by the electrodes 8"projected or extended within the clinkering furnace, the heat of which is so regulated in relation to the speed or flow and nature of the mix or calcines advanced through the clinkerin'g apparatus as to form clinker on clinkered material, which said clinker or clinkered material is discharged from the front opened end of the clinkering furnace and delivered in the present case directly into a cooler for the cooling thereof, although the treated material .outflowing from the clinkered apparatus may be delivered or conveyed to any other suitable place of deposit.

In case portions of the material advanced through the clinkered furnace and subjected to the heat of the electric are maintained therein are not melted thereby, but remain ,in a granular or semi-vitreous form, the

same may be discharged onto any suitable form of a separating device for removing oversized lumps from discharge into the cooler and which in the present. case is a cooler of the mechanically rabbled regenerative form. The heat abstracted from the hot clinkered material passing through the cooler and which discharges from the cooler as heated air, is, in the present case, con veycd and delivered into the calciner adjacent the zone of combustion therein by means of the conduit 22 and is utilized in the calciner as secondary air of combustion for the fuel needed or required in the calciner for the calcination of the raw mix of material passing therethrough for treatment.

If so desired, the electric clinkering furnace may be employed for actually melting the mix delivered thereto and passing therethrough and in such case the same type of furnace may be employed as utilized for the clinkering of the mix. In this case it will not generally be required to regenerate much of the heat of the product in the secondary air for combustion in the calciner, but in general it is always advisable to cool the product to as great an extent as possible by passing the preheated secondary air in proximity to it, thus heating the air and thereby rendering the process of calcination more efficient.

IVhile I have described and illustrated a practical, economical, simple and eflicient type of electric furnace for clinkering or melting the calcined. mix delivered thereto from the calciner, I do not wish to be understood as confining myself to the particular described and illustrated constructed electric furnace nor do I Wish to be understood as confining or restricting myself as associated with the electric clinkerer to any particular type of a calcining element, and equally so, do not wish to be understood as restricting the electric clinkering apparatus as having associated therewith any particular type of a cooling element, for, as a matter of fact, the cooling element illustrated as associated with the electric clinkering furnace may be dispensed with. In brief, the invention comprises broadly the clinkering of calcined mixes for making cement or magnesite or similar materials and subjecting the hot calcines to the heat of electric arcs by progressively advancing or passing said calcines through the action of vibratory feed means through the clinkering furnace and Within the zone of the electric heat therein of a temperature sufficiently high and necessary for the making of clinkers or the melting of the calcined material with a relatively small expenditure of valuable energy.

While the described clinkering apparatus is more particularly designed for the continuous clinkering or fusing of pulverulent materials for the production of high aluminous and other highly refractory cements and a very high grade of dead-burned magnesite, it is also applicable to a Wide range in the treatment of other granular or vitreous materials whose quality will be greatly improved by a final treatment in the heat of the electric arc Within the clinkering apparatus and other heat to which the material is subjected while progressively advanced through the clinkering apparatus, but which treatment would not be economically feasible if all the heat for decomposing the raw materials and heating the same to an initial high temperature'had to be furnished from the electric energy in the first instance.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent, is:

I claim:

1. A clinkering apparatus, the same comprising an. insulated stationary elongated open-bottomed furnace structure rovided with an inlet for calcined materia and an outlet for the discharge of the clinkers, electrodes extended into the furnace for maintaining therein a temperature sufiicient for the clinkering of calcined material, a vibratory hearth associated with the furnace for receiving and advancing material to be clinkered therethrough, and 'means for imparting vibratory movement to said hearth in .a direction corresponding to the line of travel of the material from the inlet to the discharge opening.

2. An apparatus for the clinkering of material the samecomprising an insulated stationary elongated furnace provided with an inlet for material to be treated and an outlet for the discharge of c'linkers, means for electrically heating the interior thereof to la temperaturesuflicient to cause the clinkering of material passing therethrough, a longitudinally disposed vibratory hearth within the furnace for receiving and advancing material therethrough, and means for impartin vibratory movement to said hearth in a irection corresponding to the line of travel of the material from the inlet to the discharge opening.

In testimony whereof, I have signed my name to this specification.

ROBERT D. PIKE. 

